Fluidic Rectification

A device for fluidic rectification based on the inertial effects in a fluid jet formed by fluid flow issuing from a nozzle. 

A device for fluidic rectification using a series of nozzles located along a channel for issuing short puffs of flow that travel through the channel. 

In spite of the wealth of applicable principles [16, 19,22,23], current designs of microfluidic pumps are mostly operating on the simple principle the configuration of which is schematically presented in Fig. 1, mainly with the valve-less, i.e., pure fluidic rectification. Fig. 5. Much attention in the development has been devoted to suitability for... 

Valve-Less Rectification Pumps, Fig. 7 Schematic representation of the double-acting reciprocating pump driven by a full-bridge two-phase actuator. Two alternating flows, mutually phase-shifted by n radians, are rectified by four fluidic diodes coimected to form the Gratz... 

A typical present-day valve-less micropump may correspond to the example presented in Fig. 5. There is again the displacement by deformation of the compliant membrane, but the rectification is made by the fluidic suction and delivery valves, formed by cavities in the solid body of the pump. The valves shown in Fig. 5 are the Venturi diodes, currently very popular. Their rectification effect is based on the dissimilarity of the flow in the two opposite directions, as... 

Valve-Less Rectification Pumps, Fig. 13 Data collected from literature on micropumps show, somewhat surprisingly, that pumps with mechanical valves do not deliver more pumped fluid in the course of each stroke than the pure fluidic ( valve-less ) ones... 

Valve-Less Rectification Pumps, Fig. 16 Tesla diode, the earliest no-moving-part device designed to exhibit a large difference between the properties in forward and return flow direction. While the forward flow left, top) is almost straight, the reverse flow right, bottom) enters the complex curved flowpath. Diodity, even in the typical multi-stage layout, is not high, much worse than obtainable with vortex-type fluidic diodes... 

Fluidic pumping offers a wide field for potential improvements. Efficiency which, until now, has been of secondary importance, less important than manufacturing simplicity and maintenance-free operation, may become an obvious target for optimization. Besides development of new rectification principles with better diodity properties. 

Valve-Less Rectification Pumps, Rgure 1 Schematic representation of a single-action reciprocating pump. The alternating flow, shown symbolically as generated by a piston and crankshaft mechanism, is rectified by two fluidic diode valves. Their schematic symbol is derived from one of the oldest... 

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